package com.blife.util;

/**
 * Created by chen on 2017/6/19.
 * <p>
 * Email 122741482@qq.com
 * <p>
 * Describe: 系统密码 工具类
 */
public class PasswordUtil {

    public static final String HASH_ALGORITHM = "SHA-1";
    public static final int HASH_INTERATIONS = 1024;
    public static final int SALT_SIZE = 8;

    /**
     * 生成安全的密码，生成随机的16位salt并经过1024次 sha-1 hash
     */
    public static String entryptPassword(String plainPassword) {
        String plain = Encodes.unescapeHtml(plainPassword);
        byte[] salt = Digests.generateSalt(SALT_SIZE);
        byte[] hashPassword = Digests.sha1(plain.getBytes(), salt, HASH_INTERATIONS);
        return Encodes.encodeHex(salt)+Encodes.encodeHex(hashPassword);
    }

    /**
     * 验证密码
     * @param plainPassword 明文密码
     * @param password 密文密码
     * @return 验证成功返回true
     */
    public static boolean validatePassword(String plainPassword, String password) {
        String plain = Encodes.unescapeHtml(plainPassword);
        byte[] salt = Encodes.decodeHex(password.substring(0,16));
        byte[] hashPassword = Digests.sha1(plain.getBytes(), salt, HASH_INTERATIONS);
        return password.equals(Encodes.encodeHex(salt)+Encodes.encodeHex(hashPassword));
    }
}
